title: Butyric acid from anaerobic fermentation of lignocellulosic biomass hydrolysates by Clostridium tyrobutyricum strain RPT-4213.
abstract: A novel Clostridium tyrobutyricum strain RPT-4213 was found producing butyrate under strict anaerobic conditions. This strain produced 9.47 g L(-1) butyric acid from MRS media (0.48 g/g glucose). RPT-4213 was also used to ferment dilute acid pretreated hydrolysates including wheat straw (WSH), corn fiber (CFH), corn stover (CSH), rice hull (RHH), and switchgrass (SGH). Results indicated that 50% WSH with a Clostridia medium (Ct) produced the most butyric acid (8.06 g L(-1), 0.46 g/g glucose), followed by 50% SGH with Ct (6.01 g L(-1), 0.44 g/g glucose), however, 50% CSH Ct showed growth inhibition. RPT-4213 was then used in pH-controlled bioreactor fermentations using 60% WSH and SGH, with a dilute (0.5×) Ct medium, resulting 9.87 g L(-1) butyric acid in WSH (yield 0.44 g/g) and 7.05 g L(-1) butyric acid in SGH (yield 0.42 g/g). The titer and productivity could be improved through process engineering.
authors.affiliation: Renewable Product Technology Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, 1815 N. University St., Peoria, IL 61604, USA. Siqing.liu@ars.usda.gov
authors.forename: Siqing
authors.initials: S
authors.lastname: Liu
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Bischoff
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Leathers
authors.forename: Nasib
authors.initials: N
authors.lastname: Qureshi
authors.forename: Joseph O
authors.initials: JO
authors.lastname: Rich
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Hughes
mesh_terms: D000693:Anaerobiosis; D018533:Biomass; D003013:Clostridium / Q000378:metabolism*; D005285:Fermentation; D008031:Lignin / Q000378:metabolism*
chemical_list: C036909:lignocellulose; D008031:Lignin
keywords: Butyrate; Clostridium tyrobutyricum; Corn fiber; Corn stover; Rice hull and switchgrass hydrolysates; Wheat straw